Promacta (eltrombopag) is currently approved as second-line therapy for patients with severe aplastic anemia who have had an insufficient response to immunosuppressive therapy. A new study published in the New England Journal of Medicine would indicate that eltrombopag should be part of the first-line therapy for this rare disease in combination with immunosuppressive therapy.
The study by Townsley et al was a phase 1/2 study in which 92 patients with aplastic anemia given immunosuppressive therapy who were enrolled in 1 of 3 treatment cohorts:
1. received eltrombopag from day 14 to 6 months
2. received eltrombopag from day 14 to 3 months
3. received eltrombopag from day 1 to 6 months
The primary outcome was complete hematologic response at 6 months. Secondary end points included overall response, survival, relapse, and clonal evolution to myeloid cancer.
The rate of complete response at 6 months was 33% in cohort 1, 26% in cohort 2, and 58% in cohort 3. The overall response rates at 6 months were 80%, 87%, and 94%, respectively.
Table: Efficacy Outcomes
Day 14 to 6 months
Day 14 to 3 months
Day 1 to 6 months
“The addition of eltrombopag to immunosuppressive therapy was associated with markedly higher rates of hematologic response among patients with severe aplastic anemia than in a historical cohort,” concluded the authors.
Townsley DM, Scheinberg P, Winkler T, et al. Eltrombopag Added to Standard Immunosuppression for Aplastic Anemia N Engl J Med. 2017; 376:1540-1550 DOI: 10.1056/NEJMoa1613878